Mazda MX-5 1989
The Mazda MX-5 is a
popular sports car built by Mazda in Hiroshima, Japan, since 1989. It is
known as MX-5 Miata (or popularly just Miata) in North America, MX-5 in
Oceania and Europe, and Roadster (under the Eunos marque until 1996) in
Japan. The MX-5 is one of the world's best-selling sports cars, with
748,904 cars sold until the end of 2005. Beginning with the
third-generation 2006 model, Mazda consolidated worldwide (excluding
Japan) marketing using the MX-5 name, though enthusiasts in the USA (and
the company itself) still refer to it as Miata, a name that means
"reward" in Old High German.
The return of the sports roadster
The
MX-5 was envisioned by its designers as a small roadster with a minimum
of unnecessary weight and complexity, a direct descendant of the small
British roadsters of the 1960s such as the Triumph Spitfire, MG Midget,
Lotus Elan, and Porsche 550 Spider. By the early 1980s, roadsters had
all but vanished from the market, sacrificed to the increasing safety
and anti-pollution regulations everywhere. The MX-5 would thus mark the
return of the roadster, using modern technology allied to the tradition
of the roadster type.
As a result, the MX-5 has a traditional FR
(front-engine, rear-wheel-drive) layout and 4-wheel independent double
wishbone suspension. It comes with a longitudinally mounted four
cylinder engine coupled to a manual transmission (an automatic
transmission is available as an option).
The body is a
conventional, but very light, unibody shell. The MX-5 also incorporates a
unique trusswork called the Powerplant Frame (PPF) which connects the
engine to the differential, minimizing flex and creating a tight,
responsive feel. Many MX-5s feature limited slip differentials and
antilock brakes. Traction control is an option available on some models.
With an approximate 50:50 front/rear weight balance, the car has very
neutral handling, which makes it easy to drive for the beginner, and
fun for the advanced driver. Inducing oversteer is easy and very
controllable. The MX-5 is thus popular in amateur and stock racing
events, including, in the USA, the Sports Car Club of America's Solo2
autocross and Spec Miata race series.
As a measure for success,
the Guinness Book of Records declared the MX-5 Miata the world's
best-selling sports car on February 13, 2002, with more than 700,000
sold until that date.
The MX-5 has won over 150 awards in its
history, including making Car and Driver magazine's annual Ten Best list
seven times; Wheels Magazine 's Car of the Year for 1989 and 2005;
Sports Car International's "best sports car of the 1990s" and "ten best
sports cars of all time"; 2005-2006 Car of the Year Japan; and 2005
Australian Car of the Year.
There have been three generations of
the MX-5, each introducing overall changes to the exterior, interior and
mechanical components of the car: the first generation, with production
code NA, was produced from 1990 to 1997 in model years; the second
generation, NB, from 1999 to 2005; and the current third generation, NC,
from 2006.
The competition to design the MX-5
The
design of the first MX-5 was the result of an internal Mazda
competition between the two Design Studios in California, USA and Tokyo,
Japan. The role of designing an FR (front-engine, rear-wheel drive)
light-weight sports car was assigned to the California Design Studio
whilst at Tokyo two different models were entered the competition: an FF
layout (front-engined, front-wheel drive) and an MR layout
(mid-engined, rear-wheel drive).
The first round of judging the
competing designs for the MX-5 was held in April 1984. Designs were
presented on paper. The mid-engined car appeared the most impressive,
although it was known at the time that such a layout would struggle to
meet the noise, vibration and harshness (NVH) requirements of the
project. It was only at the second round of the competition in August
1984, when full-scale clay models were presented, that the California FR
design, codenamed "Duo 101", won the competition and was selected as
the basis for Mazda's new light-weight sports car.
The Duo 101
design, so named as either a soft-top or hard-top could be used,
incorporated many key stylistic cues inspired by the Lotus Elan, a 1960s
roadster widely considered as one of the best-handling sports cars of
its day. International Automotive Design (IAD) in Worthing, England was
commissioned to develop a running prototype. It was built with a
fiberglass body, a 1.4-liter engine from a Mazda Familia and components
from a variety of early Mazda models. The prototype was completed in
August 1985.
After some minor changes in the design, the project
received final approval on January 18, 1986 and the car was now
codenamed P729. The task of constructing five engineering mules (more
developed prototypes) was again allocated to IAD, which also conducted
the first front and rear crash tests on the P729. The project was moved
to Japan for final engineering details and production issues to be
decided. The MX-5 was almost ready to be introduced to the world as a a
true light-weight sports car, weighing just 940 kg (2070 lb).
First Generation (NA)
The
MX-5 was unveiled at the Chicago Auto Show on February 10, 1989, with a
price tag of US $13,800 (US $22,650 in 2006 adjusted for inflation).
The MX-5, with production code NA, would be available for delivery to
buyers on July 1989 as a 1990 model. An optional hardtop was made
available at the same time, in reinforced engineering plastic.
In
Japan, the car was not badged as a Mazda, as the company was
experimenting with the creation of different marques for deluxe models,
similar to Nissan's Infiniti and Toyota's Lexus. Instead, the Mazda MX-5
was sold as the Eunos Roadster in that market.
The body shell of
the NA was all-steel with a light-weight aluminium hood. Overall
dimensions were 3970 mm (156.3 in) in length, 1675 mm (65.9 in) in
width, and 1235 mm (48.6 in) in height. Drag coefficient was indicated
as 0.38, reasonably aerodynamic. Suspension was an independent double
wishbone on all four wheels, with an anti-roll bar at the front. Four
wheel-disc brakes, ventilated at the front, were behind alloy wheels
with 185/60HR14 radial tires.
The original MX-5 came with a
1.6-liter double overhead cam inline four-cylinder engine, producing 90
kW (120 hp) and 100 ft·lbf (136 N·m) of torque. The engine employs an
L-Jetronic fuel injection system and a camshaft angle sensor instead of a
distributor. This engine, codename B6, had been previously used in the
323 series, including the 323 GTX, a turbocharged, all-wheel drive
vehicle, and retained the reinforcements and under-piston oil sprays
required for aftermarket turbocharging.
Standard transmission was
5-speed manual. Japan and the USA got an optional automatic transmission
which proved unpopular; these markets also received an optional viscous
limited slip rear differential.
The NA could reach 96 km/h (60 mph) in 9.4 s and had a top speed of 190 km/h (119 mph).
For
the 1994 model year, the first-generation MX-5 was freshened with the
introduction of the more powerful 1.8-liter BP engine, dual airbags and a
geared, torque-sensing limited slip differential in some markets. The
chassis was substantially braced to meet new side-impact standards, most
obviously by adding a bar between the seatbelt towers inside the car,
but also to the front and rear subframes. No exterior changes were made,
though. This is called the NA Generation 1.5.
The new engine
produced 98 kW (130 hp), increased to 133 hp (99 kW) from 1995. The base
weight increased to 990 kg (2180 lb). Performance was improved
slightly, the additional power being partly offset by the extra weight.
In some markets such as Europe, the 1.6 engine continued to be available
as a lower-cost option, but was detuned to 88 hp (66 kW). This
lower-powered model did not receive all the additional chassis bracing
of the new 1.8. Japanese and US cars were fitted with an optional Torsen
LSD, which was far more durable than the previous viscous differential.
There
were a number of trim levels and special editions available, determined
by local Mazda marketing departments. In the US, the base model was
called the "A Package". A "B Package" added some options, while the "C
Package" included a tan interior and top and leather seats. The "R
Package" was for racing, and the annual special editions were formalized
as "M Editions" from Generation 1.5. These included all of the luxury
options from the "C Package" as well as special paint and, sometimes,
special wheels.
The first generation MX-5 was phased out with the
1997 model year (there was no 1998 model year), with the final 1500 NAs
produced for the US market being the "STO" ("Special Touring Option")
versions.
Second Generation (NB)
In 1998,
Mazda released the second-generation MX-5, production code NB, for the
1999 model year. The NB featured a more powerful engine and, on the
exterior, more modern styling cues borrowed from the 1992 Mazda RX-7
model. Prices in the United States, the main market for the MX-5,
started at US $19,770 (US $24,680 in 2006).
Although many parts of
the interior and body were different, the most notable changes were the
headlights: the first generation's retractable headlights had been
exchanged for fixed ones. The new car had grown slightly in width
compared to the earlier model with dimensions: length 3955 mm (155.7
in); width 1680 mm (66.1 in); height 1235 mm (48.6 in) and wheelbase
2265 mm (89.2 in). Without options, the NB weighed exactly 1000 kg (2205
lb). The new generation was slightly more aerodynamic than the
original, with a Cd figure of 0.36.
The NB continued to employ
four-wheel independent suspension, with enlarged anti-roll bars at the
front and rear, but the wheels, tires and brakes were significantly
upgraded: ABS was offered as an option; alloy wheels were now 14 in or
15 in in diameter and 6 in in width, depending on the trim package;
sports models were equipped with the larger wheels and 195/50VR15 tires.
The
BP-4W engine remained at 1.8 L but received several minor updates. The
engine compression ratio was raised from 9.0:1 to 9.5:1 by adding
slightly domed pistons. The intake cam was changed to a solid lifter
design with a stronger cam. The intake runners in the head were
straightened and the intake manifold was mounted higher up. Mazda's
Variable Intake Control System system was introduced, which effectively
gave a long narrow intake mainfold at low rpm for better swirl, changing
to a short, free-flowing manifold at high rpm for maximum breathing.
Power output of the new engine was quoted at 105 kW (140 hp) with 119
ft·lbf (161 N·m) of torque.
The 1.6 B6 engine remained available in some markets, including Europe and Japan.
The 1.8 NB could reach 96 km/h (60 mph) in 7.9 s and had a top speed of 197 km/h (123 mph).
In
1999, Mazda celebrated the 10th anniversary of the MX-5 with the 10th
Anniversary Model, a limited edition featuring some until-then exclusive
features, namely a six-speed transmission and Bilstein shock
absorbers,; performance figures were slightly different, with faster
acceleration but lower top speed than the standard 1.8 NB.
For the
2001 model year, a facelift to the Second-Generation MX-5 was released.
There were some minor exterior changes, with a press-release of July
18, 2000 announcing the changes as "resulting in an even sportier and
more forceful look". Thus Generation 2.5 was born. Some cockpit elements
were also changed, with instrument panel gauges having a white face and
red numbers. The seats were also upgraded, incorporating more support
in the side bolsters, and taller headrests. Added for top models were
16-inch wheels with 205/45VR16 low-profile tires and larger brakes at
the front and rear. The upgraded tires and suspension allowed the new
model to pull 0.88 g in lateral grip in tests by Car and Driver
magazine. The body was strengthened, gaining 16% in bending rigidity and
22% in torsional rigidity. With the minimum of options, the 2001 model
weighed 1065 kg (2350 lb).
The 1.8 BP-Z3 engine was slightly
modified and now featured variable valve timing on the intake camshaft.
The intake and exhaust system also received a minor upgrade. These
modifications resulted in a power output of 117 kW (155 hp) (Japan and
Australia) or 110 kW (146 hp) (US and Europe). In the United States,
Mazda erroneously quoted the power figure for the Japanese and
Australian model in early catalogues. Car and Driver magazine and
numerous owners confirmed the missing power, and Mazda was forced to
offer to buy back the 2001 cars due to those misleading power claims.
Owners who did not take up the buy back offer were offered an apology
and free servicing for the warranty period.
In 2001, Mazda
Australia produced locally a limited run of 100 turbocharged MX-5s
labelled the SP. Over 215 parts went into upgrading the performance of
the SP creating a powerful sportscar that looked identical to a standard
MX-5. The driveline, braking, suspension and engine internals remained
standard. The upgraded engine was rated at 157 kW (201 hp).
The
2004 model year saw the introduction of the official turbocharged
Mazdaspeed MX-5, Roadster Turbo in Japan. It featured a light-pressure
turbo BPT engine for 178 hp (133 kW). Other features included a special
suspension, upgraded transmission and clutch assemblies, upgraded
drivetrain components, Racing Hart 17-inch wheels, special interior
trim, and special exterior paint. 5,428 Mazdaspeed MX-5s were produced
during model years 2004 and 2005.
Still in the 2004 model year, a
division of Mazda in Japan produced a limited run of 350 Roadster Coupés
with an integral hardtop roof, effectively making this a coupé instead
of a roadster. The body structure was reworked to incorporate the roof
for a substantial increase in chassis rigidity and a weight increase of
10 kg (22 lb). No Roadster Coupes were exported outside Japan.
Third Generation (NC)
Production of the third-generation MX-5, code NC, began May 17, 2005, for delivery in August, for the 2006 model year.
Despite
the success in maintaining enough external similarities, the third
generation shares no components with the second generation, except for
the side-panel turning-lights on the European-spec models. It can thus
be considered an all-new MX-5. The suspension was changed from a 4-wheel
double wishbone setup to a front wishbone/rear multilink setup.
Technologies like traction control and stability control were added to
increase driveability.
The exterior styling harkens back to the
original design while adopting a clean, more muscular profile. Some
design elements were adopted to reinforce the family ties with the Mazda
RX-8. Unlike the update from NA to NB, which was mostly a
nose/tail/interior change, there are substantial differences in every
body panel of the NC, so much that older-generation accessories will not
work on the NC.
For Australia and the USA, the engine was the new
16-valve, 2.0-liter MZR I4, producing 170 hp (128 kW) and 140 ft·lbf
(190 N·m), coupled to a 6-speed manual transmission. For Europe, two
engines are offered: the same 2.0 MZR, but producing 160 hp (118 kW) and
188 N·m; and a new 1.8 MZR, producing 126 hp (93 kW) and 167 N·m,
coupled to a 5-speed manual transmission.
A 6-speed automatic
transmission, with steering wheel mounted paddle shifters, is optional. A
test by Car and Driver magazine revealed a 0-97 km/h (0-60 mph) time of
6.5 s for the 2.0 NC.
The NC was launched with a special edition
called "3rd Generation Limited" which featured added chrome accents and
special wheels. 3500 were built worldwide (300 in the UK, 750 in the
USA), delivered in advance of standard models.
On 18 July 2006,
Mazda unveiled a coupé convertible version of the NC with a three-piece
folding hardtop. The British International Motor Show was the venue
chosen for the world premiere of the new model, named MX-5 Roadster
Coupe in Europe, Roadster Power Retractable Hard Top in Japan, and MX-5
Miata Power Retractable Hard Top in the USA.
Adding 37 kg (82 lb)
to the weight of a comparable model with soft top, the hard top takes 12
seconds to raise or lower; in a departure from the competition, it does
not take any of the existing trunk space when folded down. The price
premium is expected to be less than the cost of a separate hard top.
Production numbers
The
250,000th MX-5 rolled out of the factory on November 9, 1992; the
500,000th, on February 8, 1999; the 750,000th, on March 2004.
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